M2i: Anticholinergics (Anti-Muscarinics)

Mode of Action

  • Bind reversibly to muscarinic cholinergic receptors
  • Competitive inhibition
  • ∴effect can be overcome by ↑[ACh]
  • Dose of anticholinergic has little effect at nicotinic receptors∴thought of as anti-muscarinic
  • Naturally occurring tertiary amines: ATROPINE, HYOSCINE
    • Cross BBB
    • Central effects: sedation, amnesia, anti-emesis, central cholinergic syndrome
  • Synthetic quaternary amines: GLYCOPYROLATE → cannot cross BBB
GLYCOPYROLATE